Overpopulation cannot cause death by starvation, because the human body has a mechanism to prevent starvation death when food is limited.

Every day, human beings starve to an early death.

How does this happen?

We know that for every person that starves to death in th eworld today, there is plenty of excess food that goes unused and uneaten, more than enough to have kept that person alive.

Any large scale starvation to death only occurs as a result of disaster causing an abrupt stoppage of resources, or as a result of human choice not to redistribute resources.

To test this, consider a thought experiment given these parameters: in a closed community of people, food is distributed to each individual according to need. To mimic a starvation scenario caused by finite supply and population but not by natural disaster, we keep the rate of food production constant and the population's desire to reproduce constant.

Given a supply of food, the people in the thought experiment will naturally multiply. As they multiply, they will eventually start using all of the food supply. As they continue to multiply, each person's share of food is decreased.
This will contnue to happen until population is high enough to mean that each full grown person will lose weight.

Eventually, each grown individual loses weight and begins losing fat stores.As the sexually mature women lose weight and fat stores, they become infertile. As a result of infertility, population ceases to rise.

Thus, the body makes reproduction impossible in the absence of excess, and therefore, rising population cannot cause death by starvation because people become infertile because they starve to death. As female athletes often prove, a woman can be infertile yet quite fit and healthy until she reaches old age.

The biological mechanism is that the human body becomes infertile before it starves to death..

The purpose of this conversation is point out that how we treat each other is more critical to our survival than any population number we attempt to adopt.

Nov 11 2013:
Your argument is flawed because it doesn't include greed, power, war, natural disaster, lack of clean water, infrastructure to transport food and other such items. You are right that most people who are starving don't die from starvation but from side effects like infection due to lowered immune system. The effects of starvation go beyond the individual that is starving, it creates lowered output because they cannot work hard enough to provide for their families. If you are a farmer and have to work long hours you need more calories to do your work than a lawyer or doctor, but if you go through a bad year because of drought, then you might not produce enough food to provide for your family and have enough seed left over to plant next year's crops. You might have to kill your ox for food and then tilling the field becomes impossible.

Nov 12 2013:
Thanks for your comments, Scott. I actually do account for those things. The point of this coversation is to isolate the role of population. To do this, we assume constant level of food supply and we assume even distribution. That is completely intentional, because by doing so we can examine what will happen as population grows. Isolating a variable can help us better understand the complex system.

In terms of population, we can see that the human body becomes infertile when excess dissappears. Because of this, when food supply declines, population declines, and could, at certain rates, do so without one person starving to death.

The point is to understand how to minimize premature death by starvation.

To do so, we need to find ways to maintain constant food supply, making the resource use sustainable. Eventually we would be finding ways to make the modern lifestyle as sustainable as possible with the least amount of fossil fules as possible. We have to manage and prevent pollution.

We must also find ways to redistribute resources as evenly as possible. When we combine this goal with the goal of sustainability, the principle of democracy surfaces. It is the model that makes it more likely to attain more even resource use, and do so long term because the people themselves are empowered.

In other words, hopefully we can finally put an end to Malthusian scaremongering once and for all, and turn to the very real goals of sustainability and democracy.

Nov 8 2013:
18th century scholar Thomas Malthus predictions of overpopulation leading to massive worlwide starvation, despite not coming to pass have lingered on until now. Some still ascribe to them. Simply put from Malthus' arguments the claim remains that exponential population growth is destined to overtake food production.

While it is true that exponential curves increase more quickly than, say linear growth, human population growth is not perfectly exponential. My opening statements explain why: humans depend on food excess to be fertile in the first place.

Nov 8 2013:
Democracy is likely the most effective, proven way to distribute food and other resources evenly and in better amounts. Yes there are always outliers and bureacrats skimming off the top, but in this case the people have a mechanism to avoid complete elitist control of resources.

And yes, food won't likely be distributed uniformly on a global scale, but we can get better at being closer to uniform.

Nov 12 2013:
18th century scholar Thomas Malthus predictions of overpopulation leading to massive worlwide starvation, despite not coming to pass have lingered on until now. Some still ascribe to them. Simply put from Malthus' arguments the claim remains that exponential population growth is destined to overtake food production.

While it is true that exponential curves increase more quickly than, say linear growth, human population growth is not perfectly exponential. My opening statements explain why: humans depend on food excess to be fertile in the first place.

(Comment posted 3 days ago but added here in case you did not see it.)

Nov 12 2013:
Thank you for adding your comment again via reply function, as I didn't come back here so far and would, most likely, not have noticed otherwise.

I understand now the motivation of your idea and like to point out, that its base is only valid under steady state conditions and without abrupt changes within food production. A single harvest below average can already cause starvation, the moment the minimum calories produced drops under the minimum calories needed to maintain malnutrition above lethality levels.

A very sensitive equilibrium and many variables are either in gray-scale, such as fertility dropouts and food distribution equality, or even unpredictable, such as harvest results, which all together should not be confused with a save, harmless and automatic 'stabilization mechanism' in human population.

The great famine in Ireland between 1845 and 1852, also known as the 'Irish Potato Famine', is exemplary, that sudden drops in food supply, caused at that time by a potato pest, can not be adjusted to via fertility adaptation, as the harvest result already cuts to short on the existing population.

Also important is the given and exclusive dependency of our worldwide food production on fossil fuels and the fact, that nobody can foresee its decreasing behavior, which effects the price development, which effects the cost of food and which may also result in the situation, that the leached out soil wasn't productive enough for conventional farming methods without fossil fuels before alternative farming would manage to cope with it. If this happens suddenly, within a view years, fertility couldn't cope with it either and mass starvation would be the result.

All in all a theoretical method which we should carefully examine to learn from, yet not to rely on. But without doubt a very interesting theory indeed!

Nov 8 2013:
I have travelled across India. looking for starvation.
I hope to soon travel across Africa in search of the same.
Let me tell you what I found in India.
There is NO starvation.
There is plenty of malnutrition. But never starvation.
I tried to ask my friends who have gone to Africa about starvation.
Well almost all agree that starvation in Africa is mainly due to wars.
Starvation was due to disruption of supply channels and hoarding of food mainly by warring parties.
Do take this into consideration.
Maybe the only thing we need to do is avoid any forms of war on any reason.
People will always find a way to eat. and slowly also solve the malnutrition problems.
The human spirit is always strong.
It can only be disrupted by inhuman behavior during wars.

Malnutrition is painful. I got a glimpse of it when I was pregnant with twins. Fortunately I was able to recieve several iron transfusions to keep me healthy and strong as my body was growing two babies.

Definitely nutrition is an essential aspect of sustainability. The efforts to grow cheaper, fatter wheat for example are creating a dearth in wheat nutrients. So people are getting more fat instead of feeling better from the essential nutrients making their bodies function as they should.

Nov 8 2013:
Do you know the book Poor Economics by Banarjee and Duflo, of MIT's Poverty Action Lab? They have done research into this question and come to your same conclusion. Malnutrition in the sense of inadequate consumption of micronutrients, particularly in the diets of the young, is the hunger issue outside of areas affected by war and natural disaster.

Nov 11 2013:
those conditions compound however, malnutrition leads to lowered intelligence especially during critical developmental ages. It means that the parents have to forego food to keep their children living leading to decreased output. It leads to lowered immunity so a simple bug becomes deadly. Most kids that die from starvation die from diarrhea caused by bacteria that any healthy person could fight off. Starvation goes hand in hand with poor quality water which is a death sentence.

Also, you didn't look hard enough because starvation is definitely out there and india is a big place

Nov 12 2013:
Bedouins live in deserts, Eskimos live in icy land. I can give you many such examples where humans have learned to live within limited resources.
Starvation is last days of living without food.
Malnutrition is living with limited variety of food.
Do not underestimate the will of humans to survive and the ability to search for food.
Humans are today only limited on this ability by artificial borders created and manned by military forces and wars.
I have seen people in India drinking water directly from water wells and stay healthy while me and my colleagues from developed countries got diarrhea and stomach pain within 2 days of drinking that same water.
The bodies of these fantastic people have better immunity to whatever inside that water while our own body from advanced civilization does not.
India is indeed a big place but assuming there is starvation and making policy based on such assumption is just bad policy.
Western civilization kill everything and live happily. Yes.
But this people have learned and adapted their body to live among all living things including bacteria and virus and what not.
I have seen women pouring milk into snake pits and pray that it does not harm their family.
They do not even kill snakes.
We should not use our limited knowledge in medical science to apply theories to people who have had a longer civilization that survives difficult conditions.
And if our climate science is true than we may all soon face problems with food supply and difficult conditions soon. We can learn a few things from this great people. Let's not be arrogant.

Nov 8 2013:
I am seeking a solution that fuses consequentialist ethics with deontoligical ethics: finding what is good for all without doing it through harmful means.

To wit: the model I describe, where population stabilisation occurs without starving anyone to death is dependent upon certain things happening: first, everyone being given according to need, second, a sustained constant food supply. This model does not get us off the hook of being responsible for sustainability, but it doesn't get us off the hook of defending human rights, either. The variables assumed in the model are actually the roadmap.

Nov 8 2013:
The problem is that death via starvation isn't a result of population size except in extreme cases. Its usually a result of a disrupted food supply--natural disasters, crops failing, or even malicious intent during times of war. A smaller population size gives you a wider safety buffer (easier to scrounge up enough food in an emergency), no more, no less.

Hardening the food supplies is a much more effective course of action than regulating population size one way or the other. I suppose the two don't contradict, but given how hard regulating population size can be, its obvious which solution should be pursued first.

Either way, food will never be distributed uniformly on an international scale. After all, what's the point of being a military or economic major power if your population is slumming it with the starving masses? Defeats the whole purpose of hoarding power.